Vibrating switch

ABSTRACT

A switch which is operable responsive to impact comprises a ring-shaped contact biased into bridging contact with spaced stationary contacts. The ring-shaped contact is rotatable relative to the spaced contacts to present new contacting surfaces upon rotation, and is biased toward the stationary contacts by the pressure of leaf springs pressed against the ring contact by an adjustable screw which passes through the center of the contact.

United States Patent Parlato 1 June 20, 1972 [54] VIBRATING SWITCH [72]inventor: Philip .I. Purl-to, Kings Park, NY.

[73] Assignee: Alarm Products International, Inc., Long island City. NY.

[22] Filed: March 16,1971

[2i] Appl.No.: l24,791

[52] US. Cl. ..200/6l.45 R, ZOO/61.93

[51] Int. Cl. ..H0lh 35/14 [58] Field of Search ..200/6l.45-6 l .53,

ZOO/61.93; 340/26l, 262, 276

[56] References Cited UNITED STATES PATENTS 2,236,689 4/ 1941 Lemire eta] ..200/61 .49

3,389,236 6/1968 Guthart ..200/61.48

Primary Examiner-Robert K. Schaefer Assistant Examiner-M. GinsburgAttorney-Ostrolenk, Faber, Gerb 81. Solfen ABSTRACT A switch which isoperable responsive to impact comprises a ring-shaped contact biasedinto bridging contact with spaced stationary contacts. The ring-shapedcontact is rotatable relative to the spaced contacts to present newcontacting surfaces upon rotation, and is biased toward the stationarycontacts by the pressure of leaf springs pressed against the ringcontact by an adjustable screw which passes through the center of thecontact,

7 Claims, 3 Drawing Figures VIBRATING swrrcrr BRIEF SUMMARY OF THEINVENTION This invention relates to a switch device which is operableresponsive to impact forces, and more particularlyrelates to a switchfor use in a burglar detection system. It is known to mount switches onstructures which will be subject to impact forces during the forcedentry of an enclosure. A typical switch of this type is shown in U. S.Pat. No. 3,389,236 to Guthart, issued June I8, 1968.

The present invention provides a novel switch which is operated byimpact, whereby a circuit can be momentarily interrupted, or closed,thereby to activate detection and/or alarm equipment. The switch of thepresent invention incorporates a ring-shaped contact whichmakes bridgingcontact with a pair of spaced contacts. A novel centrally disposedbiasing spring structure is then pitted across the center of theringshaped contact to adjustably bias the contacts closed. The use ofthe ring-shaped contact substantially simplifies theswitch structure andpermits the use of a minimum number of parts of very high reliability.Moreover, the contact ring can be rotated relative to the stationarycontactsto present new contact surfaces after extended use and pittingof the ring which would otherwise interfere with its best operation.

BRIEF DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION OF THE DRAWINGSThe switch of FIGS. 1, 2 and 3 is mounted on an insulation base whichcould, for example, be a molded ceramic body having preformed integralextensions and openings. Thus, base 10 has side ribs 11 and 12 (FIGS. 1and 2) and pairs of cylindrical extensions 13-14 and -16, respectively.Extensions 13 and 14 have respective tapped openings 17 and 18,

respectively, while extensions 15 and 16 have relatively large 4openings which pass through the entire base, and which could receivefasteners used to fasten the switch assembly to a structure.Alternatively, the switch can be cemented to a structure at its base 19(FIG. 3) which may be suitably roughened. Base 10 further contains acentral integral extension 20 having a central tapped opening 21, and apair of openings 22-23 which are enlarged at the bottom of base 10. Afurther pair of clearance openings 26-27 (FIG. 1) are provided toreceive terminal screws, as will be described later.

A pair of conductive contact plates 24 and 25 are then provided, eachhaving pairs of openings 28-29, 30-31, and 32-33 (FIG. 1) which arealigned with pairs of elements 13-14, 22-23, and 26-27, respectively, inbase 10. Moreover, contact plates 24 and 25 are contained between ribs11 and .12 in base 10. Contact projections 35 and 36 in plates 24 and 25are thereby fixed in position relative to base 10. Contact plates 24 and25 are then held in position on the upper surface of base 10 by rivets37 and 38, respectively, or by any other suitable fastening means. Notethat plates 24 and 25 have comer cutouts 39 and 40, designed to fitaround projections 15 and 16,

respectively. t

A pair of terminal screws 42-43 are then provided with appropriatewashers 44-45, respectively, and are threaded into tapped openings 32and 33, respectively, in plates 24 and 25, respectively. The ends ofscrews 42-43 can extend into openings 26 and 27, respectively, in base10. t

A movable ring-shaped contact 46 (FIGS. 1 and 3) is then disposed on topof contact plates 24 and 25 and engages contacts 35 and 36 in bridgingcontact relation. Note that contacts 35 and 36 lie on a line whichpasses through the center of contact ring 46. Contact ring 46 is biasedinto engagement with contacts 35 and 36 by spring members 47, 48 and 49which spanthe central opening in ring contact 46 and are pressed towardring contact 46 by pressure screw 50 which passes throughalignedopenings in springs 47, 48 and 49 and is threaded into tappedopening 21in base 10. This biasing force is suitably adjusted byrotating screw 50 until the contact 46 is pressed against contacts 35and 36 with a given pressure which insures against unintentionalseparation of contact 46 and contacts 35 or 36 by impact forces lessthan a given magnitude which would be encountered during a forced entry.

An insulation cover 51 isthen provided which encloses the base 10, asshown in FIGS. 1 and 3, and which is held in place by screws 52 and 53which thread into tapped openings 17 and 18, respectively. Notethatcover 51 is easily removed to gain access to adjustment screw 50 foradjustment of contact pressure,and to contact '50 to rotate the contactto a new position relative to contacts 35 and 36. Cover 51 is furtherprovided with slots 54 and 55 (FIG. 1) in thewall thereof adjacentextensions 15 and 16, respectively. Slots 54 and S5 permit access ofelectrical leads to terminal screws 42 and 43, which leadsmust'bendaround extensions 15 and 16. Extensions l5 and 16 then blockeasy access through slots 54 and 55 to exposed conductive members withinthe cover 51.

The operation of the device should be clear since any impact forcehaving at least a component which is parallel to the axis of contact 46will, if sufficiently high, cause contact 46 to move against therestraining force of springs 47 to 49, to open its connection to one orboth of contacts 35 and 36. This will then interrupt some appropriatedetection or alarm circuit connected to terminal screws 42 and 43. Theuse of the ringshaped contact 46 pennits many economics of space andnumber of parts and permits the manufacture of a rugged and reliableswitch device, which is easily installed and adjusted.

Although. this invention has been described with respect to preferredembodiments, it should be understood that many variations andmodifications will now be obvious to those skilled in the art and,therefore, the scope of this invention is to be limited not by thespecific disclosure herein, but only by the appended claims.

1. The embodiments of the invention in which an exclusive privilege orproperty is claimed are defined as follows:

1. An impact responsive switch comprising, in combination:

an insulation base member,

contact means including a pair of fixed contacts mounted on' the uppersurface of said insulation base member and 'being spaced from oneanother;

first and second terminal means respectively connected to said pair offixed contacts;

a ring-shaped contact disposed in a plane generally parallel to theplane of said upper surface and being movable between a bridging contactengagement position and a disengaged position with'said pair of fixedcontacts;

means including resilient biasing means supporting said ring-shapedcontact for translation movement in the direction along the axis of saidring-shaped contact and normally biasing said ring-shaped contact towardone of said bridging contact engagement and disengagement positions;said ring-shaped contact being movable responsive to impact forceshaving components directed in the direction along said axis of saidring-shaped contact to the other of said bridging contact engagement anddisengagement positions; said ring-shaped contact being rotatablyadjustable relative to said resilient biasing means to present newcontact surfaces with said pair of fixed con- 18018.

2. The impact responsive switch of claim 1 wherein said means includingsaid resilient biasing means includes a plurality of stacked springplates disposed above said ring-shaped contact and bearing against thetop thereof anda support of said base member, thereby to press saidspring plates against said ring-shaped contact to bias said contacttoward said position of bridging contact engagement.

3. The impact responsive switch of claim 1 wherein said contact meansincludes first and second flat conductive plates spaced from one anotherand secured to symmetric and spaced regions of said upper surface ofsaid insulation base member; said pair of fixed contacts beingrespectively disposed on adjacent end regions of said first and secondflat conductive plates; said first and second terminal means beingconnected to opposite end regions of said first and second plates.

4. The impact responsive switch of claim 1 which includes a cover memberfor enclosing at least said upper surface of said base member, saidfixed contacts, said movable ring-shaped contact, and said resilientbiasing means; said base member having first and second integral raisedsections extending from said upper surface thereof for contacting aninterior surface of said cover member.

5. The impact responsive switch of claim 1 wherein said pair of fixedcontacts are spaced from one another along a line; the said axis of saidring-shaped contact bisecting said line.

67 The impact responsive switch of claim 2 which includes a cover memberfor enclosing at least said upper surface of said base member, saidfixed contacts, said movable ring-shaped contact, and said resilientbiasing means; said base member having first and second integral raisedsections extending from said upper surface thereof for contacting aninterior surface of said cover member; removal of said cover memberexposing said support screw for adjustment.

7. The impact responsive switch of claim 6 wherein said contact meansincludes first and second flat conductive plates spaced from one anotherand secured to symmetric and spaced regions of said upper surface ofsaid insulation base member; said pair of fixed contacts beingrespectively disposed on adjacent end regions of said first and secondflat conductive plates; said first and second terminal means beingconnected to opposite end regions of said first and second plates.

1. The embodiments of the invention in which an exclusive privilege orproperty is claimed are defined as follows:
 2. The impact responsiveswitch of claim 1 wherein said means including said resilient biasingmeans includes a plurality of stacked spring plates disposed above saidring-shaped contact and bearing against the top thereof and a supportscrew; said support screw extending serially through said spring platesand through the center of said ring-shaped contact and being terminatedby threading into said upper surface of said base member, thereby topress said spring plates against said ring-shaped contact to bias saidcontact toward said position of bridging contact engagement.
 3. Theimpact responsive switch of claim 1 wherein said contact means includesfirst and second flat conductive plates spaced from one another andsecured to symmetric and spaced regions of said upper surface of saidinsulation base member; said pair of fixed contacts being respectivelydisposed on adjacent end regions of said first and second flatconductive plates; said first and second terminal means being connectedto opposite end regions of said first and second plates.
 4. The impactresponsive switch of claim 1 which includes a cover member for enclosingat least said upper surface of said base member, said fixed contacts,said movable ring-shaped contact, and said resilient biasing means; saidbase member having first and second integral raised sections extendingfrom said upper surface thereof for contacting an interior surface ofsaid cover member.
 5. The impact responsive switch of claim 1 whereinsaid pair of fixed contacts are spaced from one another along a line;the said axis of said ring-shaped contact bisecting said line.
 6. Theimpact responsive switch of claim 2 which includes a cover member forenclosing at least said upper surface of said base member, said fixedcontacts, said movable ring-shaped contact, and said resilient biasingmeans; said base member having first and second integral raised sectionsextending from said upper surface thereof for contacting an interiorsurface of said cover member; removal of said cover member exposing saidsupport screw for adjustment.
 7. The impact responsive switch of claim 6wherein said contact means includes first and second flat conductiveplates spaced from one another and secured to symmetric and spacedregions of said upper surface of said insulation base member; said pairof fixed contacts being respectively disposed on adjacent end regions ofsaid first and second flat conductive plates; said first and secondterminal means being connected to opposite end regions of said first andsecond plates.